In May 2015, the chief executive of the NHS, Simon Stevens, claimed that the entire NHS deficit of £822m in 2014-15 could be accounted for by the “run-up in temporary staffing costs”. Six months into the new financial year, hospitals had overspent by £1.6 billion, the largest NHS deficit ever recorded.

In its report, the hospital regulator, the Trust Development Authority and Monitor, points to ever-growing demand – highlighting an 8% increase in the number of people waiting for treatment, 5% more ambulance calls and a quarter of a percentage point increase in A&E attendances than a year before. “These pressures”, the report says, “coupled with high agency costs for the additional staffing to meet that demand” have compromised the ability of hospitals to manage their finances.

The cost of agency staff has been singled out as the main culprit. Companies providing temporary staff have been accused by the health secretary Jeremy Hunt of “ripping off” the NHS, citing “unscrupulous companies charging up to £3,500 a shift for a doctor”.

The government’s response has been to impose price caps on the hourly rate paid to agency staff. From April 2016, the hourly rate the NHS can pay agency staff will be capped at 55% above the pay levels of permanent staff. Maximum rates have been set out for each staff group. The solution is appealingly simple, but it won’t solve the problem.